Help identifying these pistons

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Budgetmoparman

Budgetmoparman

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Can anyone tell me what these pistons are? I got them from a guy a few years ago. All I know is that they were out of a 383 and they are .030 obviously. I can't find any other markings on them. The numbers cast inside look like 295-99 but it is hard to tell.

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L2350 is an old trw or sealed power number. Forged piston by the looks of it. Also looks like the valve and piston had a run in.
 
Budgetmoparman said:
Can anyone tell me what these pistons are? I got them from a guy a few years ago. All I know is that they were out of a 383 and they are .030 obviously. I can't find any other markings on them. The numbers cast inside look like 295-99 but it is hard to tell.

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TRW brand. Now owned/bought out by speed-pro.

qkcuda said:
L2350 is an old trw or sealed power number. Forged piston by the looks of it. Also looks like the valve and piston had a run in.
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Eh I don't know. The both speed-pro and TRW marked the forged versions with an "F" after the number, so it would read L2350-F or L2350F depending on when it was made. I don't see an F there. So probably not forged.

As for the pistons themselves, they're pretty much a stock spec rebuild piston, or at least pretty close to stock. If I had to guess, someone decked the block, thin gasketed it to try and bump power and put the valve into the piston. Its pretty much useless. Also, the L2350's aren't made any more so finding a single one to replace it would be more difficult.
 
That looks Like a very faint hint of an F before the .030 marking> You may want to try a little Dyekem or Prussian Blue and rub it in to see if it shows, but it looks like every TRW forging I have ever seen by its markings. It appears to have extrusion lines under the head, and the numbers inside look to be coined in place.
 
Garrett Ellison said:
That looks Like a very faint hint of an F before the .030 marking> You may want to try a little Dyekem or Prussian Blue and rub it in to see if it shows, but it looks like every TRW forging I have ever seen by its markings. It appears to have extrusion lines under the head, and the numbers inside look to be coined in place.
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I'm not seeing it, and I'm on 3, 32 inch monitors?
 
What appears to be a decimal point looks more like the bottom of a weak capital F stamp when the picture is zoomed out. It may be light and shadow with the camera angle, but the decimal marks usually aren’t that large and are closer to the oversize markings.
 
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Garrett Ellison said:
Wager appears to be a decimal point looks more like the bottom of a weak capital F stamp when the picture is zoomed out. It may be light and shadow with the camera angle, but the decimal marks usually aren’t that large and are closer to the oversized markings.
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yeah, even zoomed out, I'm not seeing it. Looks like a decimal to me.
 
It's not just the F that tells it's a forging. The centering hole is the first clue, and the inside picture looks smooth like a forging. A picture of the pin boss area would clinch it. I have an old TRW catalog at home, I will look it up tonight. By the way, I don't think the piston is junk just because the valve hit it, especially if it is forged. Just clean up the sharp edges.
 
I should have taken pictures of the rest of the pistons. They all have a small valve relief cut into the top but this one looks like the valve hit it, the rest of them are not mushroomed out. I don't think there is an F on the top, that is the decimal point. They were in a motor he used for drag racing. Are they worth anything or worth using? I will try load more pictures of the other pistons and the rods tomorrow, I only have these pictures on my phone right now. I'm trying to decide if I should use them to build a street motor or if I should sell them and look for something different.

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Budgetmoparman said:
I should have taken pictures of the rest of the pistons. They all have a small valve relief cut into the top but this one looks like the valve hit it, the rest of them are not mushroomed out. I don't think there is an F on the top, that is the decimal point. They were in a motor he used for drag racing. Are they worth anything or worth using? I will try load more pictures of the other pistons and the rods tomorrow, I only have these pictures on my phone right now. I'm trying to decide if I should use them to build a street motor or if I should sell them and look for something different.

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I'd get something different. There's lighter, quicker reving pistons available these days. As for value, to a guy on a budget build, they might be worth 100 bucks or so, with the rods. If you're lucky.
 
70-71 383 2 barrel (non HP) 1.863 compression height. You should be able to figure everything from there.
 
Indeed, they are heavy! As far as reusing them it depends on how they mic out as far as round and true. Also depends on your overall engine plan and goals, and most importantly of all, BUDGET.... it's always less expensive to use something you already have! Still a very good piston for copious amounts of artificial atmosphere, just a matter of setting the clearances beforehand in case you decide to go that route later.
 
Rusty found them They were not in my catalogs but generally 3000 series numbers were forged and 2000 were cast
The pin boss is flat so forged
 
They are usally close to the weight pf stock pistons for balancing considerations
 
You're right sorry. In the catalog some have F after the number but are not forged. Confusing
 
qkcuda said:
You're right sorry. In the catalog some have F after the number but are not forged. Confusing
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Yeah I mean those do look clean and smooth so who knows
 
IIRC, the crown thickness on most TRW forgings was in the neighborhood of .300". They were often used for a lot of stroker and high compression builds when off the shelf pistons weren't available. Cheaper at that time to mill them to fit than it was to order custom pistons.
 
Here is an excerpt from one of my old TRW catalogs. It seems like everything has an F on the end. See the legend at the bottom of the page. PF is forged.

piston catalog.jpg
 
The piston part numbers are in the far right hand column, and they all seem to have an F behind them, whether they are forged pistons or not.
 
Going on memory here, but I believe that the "L" designates a forged piston for TRW.
 
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